A.C.E.S. Critical design Review. Air-breathing Cold Engine Start

Transcription

1 A.C.E.S. Air-breathing Cold Engine Start Critical design Review 1 Alex Bertman, Jake Harrell, Tristan Isaacs, Alex Johnson, Matthew McKernan, T.R. Mitchell, Nicholas Moore, James Nguyen, Matthew Robak, Lucas Sorensen, Nicholas Taylor

2 Outline Project Objectives Design Solution Critical Project Elements Design Requirements Satisfaction Project Risks Verification and Validation Project Planning 2

3 PRoject Objectives 3 Project Objectives Design Solution Critical Project Elements Design Requirement Satisfaction Project Risks Verification & Validation Project Planning

4 Project Description Design, build, and test a system to facilitate starting a JetCat P90-SXi jet engine at a temperature of -50 F by: Controlling the temperature and mass flow rate of the fuel into the engine Ensuring that the engine electronics are within their operating temperature range Ensuring that the heating system has sufficient power to heat the fuel delivery system and engine electronics Motivation Air Force Research Lab (AFRL) competition Proof of concept for high-altitude (cold-temperature) restart for jet-powered UAS 4

5 Engine: JetCat P90-SXi Miniature Jet Engine Fuel: Jet-A, Kerosene/Oil Mixture Specifications: Maximum Thrust: 105 N Maximum RPM: 130,000 Idle Fuel Flow Rate: 0.8 g/s Maximum Fuel Flow Rate: 4.8 g/s Dimensions: Length: 240 mm Diameter: 97 mm Weight: 1050 g 24 cm 5

6 Project Scope Course Design Items AFRL Design Items Heating Control Unit Main Engine Battery Engine Sensor Board Fuel Pump Fuel Hopper Heating JetCat P90-SXi Engine Control Unit Main Heater Battery Fuel Line Heating 6 Insulated Electronics Housing Fuel Line Heating

7 Course Project Objectives Fuel Delivery System (FDS) Electronics Heating Startup Time AFRL Competition Level 1 System will control mass flow rate & temperature of fuel when placed in an environment cold-soaked to - 30 F. The electronics will be heated to 60 F after being placed in an environment cold-soaked to - 30 F. The fuel delivery and electronics heating systems objectives will be completed in less than 3 hours. Level 2 System will control mass flow rate & temperature of fuel when placed in an environment cold-soaked to - 40 F. The electronics will be heated to 60 F after being placed in an environment cold-soaked to - 40 F. The fuel delivery and electronics heating systems objectives will be completed in less than 1.5 hours. Level 3 System will control mass flow rate & temperature of fuel when placed in an environment cold-soaked to - 50 F. The electronics will be heated to 60 F after being placed in an environment cold-soaked to - 50 F. The fuel delivery and electronics heating systems objectives will be completed in less than 8 m 42 s Level 4 Entire system will be integrated with engine and successfully start within 3 hours.

8 8 Mission CONOPS

9 Project Conops HCU Low Temp Electronics Engine Battery Main Heating Battery ECU Hopper Fuel Pump 1 Cold Soak in -50 F Environment Injector Q HCU Low Temp Electronics Engine Battery Main Heating Battery ECU Hopper Fuel Pump 3 Injector Initiate Fuel Flow -50 F Boundary HCU Main Heating Battery Fuel Pump Injector 9 2 Initiate Start-up Heaters Low Temp Electronics Engine Battery ECU Hopper

10 Functional Requirements FR 1) ENERGY: An initial energy source shall provide adequate power for the fuel delivery system heating and electronics heating. FR 2.1) FDS: The Fuel Delivery System shall provide a specified fuel flow rate from 0 to 4.8 g/s ± 0.13 g/s to the engine. FR 2.2) FDS: The Fuel Delivery System shall provide fuel at a specified temperature from 60 to 115 F ± 3.6 F to the engine. FR 3) Electronics Heating: The electronics (ECU, ESB, batteries) shall be heated to their operating temperature of 60 F. FR 4.1) HCU: The Heating Control Unit (HCU) shall monitor and regulate the temperature of the electronic components and fuel delivery heating systems. FR 4.2) HCU: The Heating Control Unit (HCU) shall monitor and regulate the mass flow rate of the fuel. 10

11 Design Solution 11 Project Objectives Design Solution Critical Project Elements Design Requirement Satisfaction Project Risks Verification & Validation Project Planning

12 Design Changes since PDR Supercapacitors are no longer required due to insulation research Cryogel keeps batteries within acceptable temperature range during cooling process Fuel flow rate and temperature control added Fuel line length decreased Increased power budget 12

13 Baseline Design Engine Battery Fuel Hopper 29 cm Main Heating Battery Large Fuel Line HCU 8 cm Small Fuel Line HCU Cold Temp Batteries ECU Fuel Pump 24 cm To engine 13

14 Baseline Design Initial Energy: Main heating battery insulated in Cryogel Fuel Delivery System: Resistive heating Resistive heating wire wrapped around fuel delivery components Components insulated in Cryogel Fuel pump provides specified mass flow rate to engine Electronics Heating: Resistive heating within manufactured plastic box ESB heated by power resistors inside cowling 14 Heating Control Unit (HCU): Microcontroller powered by cold temperature batteries Controls temperature of fuel delivery and electronics systems Controls fuel flow rate into the engine HCU remains functional at -50 F

15 Process Flow Diagram Cold temperature batteries provide power to the HCU HCU commands main heater battery to provide power to heating elements Electronics and FDS are heated ECU & ESB reach operational temperature as dictated by HCU Fuel in hopper and in fuel lines reaches desired temperature as dictated by HCU HCU commands fuel pump to provide fuel to engine at desired rate Fuel enters engine at desired flow rate & temperature 15

16 16 Functional Block Diagram

17 Critical Project Elements 17 Purpose & Objectives Design Solution Critical Project Elements Design Requirement Satisfaction Project Risks Verification & Validation Project Planning

18 Critical Project ELements CPE 1: Ensure that main heater battery is at or above the operational temperature (30 F), while not exceeding the maximum temperature (122 F). CPE 2: Heat the engine electronics (ECU, ESB, and engine battery) to their standard operating temperatures (60 F) while not exceeding a maximum temperature of 122 F for the battery and 150 F for the ECU and ESB. CPE 3: Heat fuel in fuel delivery system to a temperature between 60 F and the 115 F (below the cavitation temperature) to provide adequate fuel flow to the engine. CPE 4: Construct a Heating Control Unit (HCU) which will control the mass flow rate and heating systems. 18

19 Main Heater Battery CPE 1: Ensure that main heater battery is at or above the operational temperature (30 F), while not exceeding the maximum temperature (122 F). 19 Project Objectives Design Solution Critical Project Elements Design Requirement Satisfaction Project Risks Verification & Validation Project Planning

20 Battery Model Outside air temperature set to -50 F Cryogel Insulation Plastic Battery Shell The battery was set to a temperature of 70 F Min Operational Temp: 30 F Simulation run for 1 hr Lithium Polymer Battery cools to a final temperature of about 56 F CPE min min min

21 Electronics Housing Engine Battery Fuel Hopper 29 cm Main Heating Battery Large Fuel Line HCU 8 cm Small Fuel Line Cold Temp Batteries ECU Fuel Pump 24 cm To engine 21

22 Cooling Model Outside air temperature set to -50 F. The solids and internal air set to a temperature of 70 F. Bottom face has imposed dirichlet condition of F to simulate box resting on block of dry ice. Material properties used in simulation are accurate for each component. Simulation run for 1 hr. 22

23 Electronics Cooling - Top Down Main Heater Battery Min LiPo Temp 30 F HCU Min HCU Temp -57 F 23

24 Electronics Box Heating CPE 2: Heat the engine electronics (ECU, ESB, and engine battery) to their standard operating temperatures (60 F) while not exceeding a maximum temperature of 122 F for the battery and 150 F for the ECU and ESB. CPE 3: Heat fuel in fuel delivery system to a temperature between 60 F and below the 115 F cavitation temperature to provide adequate fuel flow to the engine. 24 Project Objectives Design Solution Critical Project Elements Design Requirement Satisfaction Project Risks Verification & Validation Project Planning

25 Design Requirements FR 3) Electronics Heating: The electronics (ECU, ESB, batteries) shall be heated to their operating temperature of 60 F. DR 3.1) LiPo batteries must stay above 30 F and below 122 F at all times DR 3.2) The ESB must be above 60 F and below 150 F after the heating period DR 3.3) The ECU must be above 60 F and below 150 F after the heating period ESB ECU 25

26 Placement of Resistive Wire & Temperature Sensors 29 cm Omega NCRR resistive heating wire wrapped around components Models assume homogeneous heat distribution from wire ~21 ft of wire required Vishay/Dale 12 Ohm 15W power resistors to heat ESB (x2) Legend Resistive Wire cm Temperature Sensor 24 cm Power Resistor 11 cm

27 Heating Model Outside air temperature set to -50 F. The solids and internal air set to results from previous simulation. Bottom face has imposed dirichlet condition of F to simulate box resting on block of dry ice. Material properties used in simulation are accurate for each component. Simulation run for 8 min. 27

28 Electronics Heating - Top Down FR 2.2 Hopper Fuel Lines FR 3 Engine Battery ECU ECU Battery Temp Temp Fuel Electronics Battery Temperature Temperature Range Range 28

29 Jetcat Engine Schematic Solenoid Engine Sensor Board Engine Cowling Resistive Heaters Engine Body cm 11 cm

30 ESB Cooling Model Outside air temperature set to -50 F. The solids and internal air set to a temperature of 70 F. Material properties used in simulation are accurate for each component. Simulation run for 1 hr. Air inside the cowling is completely separate from the outside air. 30

31 Jetcat Engine Cooling ESB Solenoid Direction of Gravity 31

32 ESB Heating Model Outside air temperature set to -50 F. Air inside the cowling is completely separate from the outside air. Material properties used in simulation are accurate for each component. Initial temperature used from the cooling model 2 different 10W power resistors. Simulation run for 8 min. 32

33 Jetcat Engine Heating Operational Range Max ESB Temp ESB Solenoid FR 3 ESB warming Min ESB Temp Direction of Gravity 33

34 Design Requirements FR 1) ENERGY: An initial energy source shall provide adequate power for the fuel delivery system heating and electronics heating. DR 1.1) Initial Energy source shall provide a minimum of 110 W. Main Heater Battery 34

35 Power Budget 5000 mah, 22.2 V, 60C LiPo Battery 15 W 40 W 10 W For 30min of discharge, this battery can provide 222 W. 15 W 0.45 W Electronics Housing Power W 0.7 W ESB Power 20 W 1.75 W Total Power Budget 35 FR 1: Energy W 7 W

36 Design Requirements FR2) FDS: The Fuel Delivery System shall provide adequate fuel flow for a successful start-up sequence and continued operation of the engine. This fuel flow is specified as 4.8 g/s +/ g/s for full throttle. DR 2.1) Fuel pump must be operational DR 2.2) Fuel must be heated to decrease viscosity enough to be pumped DR 2.3) Fuel lines must not exceed 140 F DR 2.4) Fuel must not exceed 115 F when flowing through fuel pump FDS 36

37 FDS Flow Fuel Pump Fuel Hopper 89.1 F Outside air set to -50 F Fluid set to kerosene Initial fluid temperature set to 90.1 F Initial structure temperature of fuel lines set to 62.8 F 87 F < 120 F 90.1 F Aluminum temperature set to -24 F Mass flow set to 4.8 g/s 82.6 F To Engine Run for 30 s to see the cooling in the lines from hopper to engine Minimum temperature ~ 82 F 37

38 Heating Control Unit CPE 4: Construct a Heating Control Unit (HCU) which will control the mass flow rate and heating systems. 38 Project Objectives Design Solution Critical Project Elements Design Requirement Satisfaction Project Risks Verification & Validation Project Planning

39 Design Requirements 39 FR 4.1) HCU: The Heating Control Unit (HCU) shall monitor and regulate the temperature of the electronic components and fuel delivery system. DR 4.1.1) Operates at and below -50 F DR 4.1.2) Receives inputs from 8 temperature sensors DR 4.1.3) Controls output for 6 heating circuits DR 4.1.4) Signals when heated components reach operational temperatures DR 4.1.5) Regulates power output to heaters DR ) Prevents overheating DR ) Increase heating where needed HCU DR 4.1.6) Provide system ready signal FR 4.2) HCU: The Heating Control Unit (HCU) shall monitor and regulate the mass flow rate of the fuel. DR 4.2.1) Regulate duty cycle for mass flow through fuel pump

40 40 Heating Control Unit Block Diagram

41 Heating Control Unit PCB Layout Power Input Temperature and Flow Inputs Programmers and SPI connections Master Slave Heater/Pump Outputs 41 Status LEDs

42 HCU Component Breakdown Atmega32L Microcontroller (x2) TMP36 Analog Temperature Sensors (x6) LM2490T-5.0/NOPB Voltage Regulator (x1) To reduce voltage from primary lithium batteries Primary Lithium Batteries (x2) High performance at low temperature FAIRCHILD N-Channel MOSFET (x5) Can handle 60V at 30A Atmel In-Circuit Debugger (x1) NCRR Resistive Heating Wire (100ft Spool) LM317 Voltage Regulator Regulate voltage to fuel pump 42 In-circuit debugger

43 43 Software Design Implementation

44 44 Software Design Implementation

45 45 Software Design Implementation

46 46 Software Design Implementation

47 47 Software Design Implementation

48 48 Software Design Implementation

49 Software Design Implementation FR 4.1 Temperature Control 49

50 50 Software Design Implementation

51 Software Design Implementation FR 4.2 Flow control 51

52 Project Risks 52 Project Objectives Design Solution Critical Project Elements Design Requirement Satisfaction Project Risks Verification & Validation Project Planning

53 Risk Identification 1. Risk of insulation failure to sufficiently protect the heating battery 2. HCU control law does not function as intended, leading to runaway temperature 3. Fuel line stoppage due to fuel freezing 4. Fuel line cracks due to low temperature 5. Fuel line melting due to high temperature resistor wire 6. Heating wire short circuit 7. Solidworks thermal models are not accurate, leading to colder than anticipated components 8. Accidental ignition of jet fuel 53

54 Risk Assessment terminology Minimal Minor Major Hazardous Catastrophic Project Damage None None Considerable component damage Serious Irreparable Project Performance Marginal Decrease Substantial Decrease Unsatisfactory for Requirements Unsatisfactory for Requirements Unsatisfactory for Requirements Budget Impact No Cost Increase Minor Cost Increase Substantial Cost Increase Serious Cost Increase Unrecoverable Cost Increase Schedule Impact 54 None Minor Substantial Serious Unrecoverable

55 Pre Mitigation Risk Assessment Matrix Near Certainty Very Likely 7 Likely 6 Minimal Minor Major Hazardous Catastrophic Unlikely 3 5 2, 8 1. Heater Battery Insulation Failure 2. Runaway Temperature 3. Fuel line stoppage 4. Fuel line cracks 5. Fuel line melting 6. Heating wire short circuit 7. Inaccurate thermal modeling 8. Jet fuel ignition Very Unlikely 1, 4 55

56 56 Risk Mitigation #2: HCU control law malfunction leading to runaway temperature Conservative control law and/or temperature fail-safes #5: Fuel line melting due to high temperature resistor wire Testing/research to determine safe temperature for our polyurethane tubing, conservative control law to avoid approaching this temperature #7: Solidworks model inaccuracy Verification testing to confirm accuracy of models #8: Accidental fuel ignition Keep fire extinguisher ready, examine fuel lines and connections before each test

57 Post Mitigation Risk Assessment Matrix Near Certainty Very Likely Likely 6, 7 Minimal Minor Major Hazardous Catastrophic Unlikely 2, 3 1. Heater Battery Insulation Failure 2. Runaway Temperature 3. Fuel line stoppage 4. Fuel line cracks 5. Fuel line melting 6. Heating wire short circuit 7. Inaccurate thermal modeling 8. Jet fuel ignition Very Unlikely 1, 4, 5, 8 57

58 Verification and Validation 58 Project Objectives Design Solution Critical Project Elements Design Requirement Satisfaction Project Risks Verification & Validation Project Planning

59 Previous Tests Performed HCU Battery Test Verified nominal battery operation at -50 F Battery was able to maintain 3.6±0.1V drop Fuel Pump Control Test Verified feasibility of fuel pump control Demonstrated linear relationship between voltage input and mass flow rate FR 4.2 Mass Flow Rate Control Result of accidental battery discharge via multimeter 59

60 Tests to be Performed All tests are designed to prove level 3 feasibility - cold soak to -50 F, 8 min 42 sec startup Test Environment Environmental Chamber Dry Ice Chamber Dry Ice and Cottonseed Oil Bucket AFRL Test Chamber Applicable Tests -Main heater battery with wiring and insulation -HCU operation -Full box integration and validation -Fuel lines integrity -Fuel pump verification of operation -Final system integration with JetCat engine 60

61 Available TEst Environments Environmental Chamber Dry Ice Chamber Liquid Cold Soak Chamber Q Q Q Available Planned to be built 61

62 Dry Ice Test Bed Overview of Testbed: Cooler Internal Chamber Temperature of ~-50 F Provides the ability to run fuel delivery system tests without risk of damaging expensive test equipment Applicable tests: Fuel line integrity HCU operation Full box integration and validation Q Q 11.5 in Q 14 in 62 Dry Ice

63 MOdel Validation Model Validation and Requirements Verification Internal Chamber Temperature of ~-50 F Fuel Flow Sensor Validate mass flow rate of fuel out of electronics box 6 Channel DAQ connected to R-type thermocouples Validate individual component surface temperatures Test Chamber Temperature sensor Verify -50±0.5 F ambient air temperature is met Q Q Temperature and mass flow rate values will be compared to models at identical points for validation Q 63 Dry Ice

64 Instrumentation Requirements Equflow 0045 Flow Rate L/min with 110,000 pulses/l (± g/s) Requirement: ±0.13 g/s NI DAQ USB R-type thermocouples ±2.7 F, +/-1V accuracy of 1.53mV Requirement: ±3.6 F Q Q Omega Type J-K Thermocouple Q Accuracy of ±0.05 F Requirement: ±0.5 F 64

65 Equflow 0045 Verification of Functional Requirements Verifies FR 2.1 and 4.2 NI DAQ USB-6009 Verifies FR 1.0, 2.2, 3.0, and 4.1 Q Q Omega Type J-K Thermocouple Verifies the customer specifications for ambient air conditions ALL FUNCTIONAL REQUIREMENTS VERIFIED Q 65

66 Test Safety Summary Risk assessment and mitigation procedures will be outlined in respective test plan All tests involving fuel or other flammable liquids will be performed in an open outdoor environment with extinguishing equipment ready All fuel and electrical connections will be checked and tested prior to full tests Risk assessments, risk mitigation, and all other safety procedures shall be outlined in the test plans and will be reviewed by a member of the PAB for approval 66

67 Project Planning 67 Project Objectives Design Solution Critical Project Elements Design Requirement Satisfaction Project Risks Verification & Validation Project Planning

68 Organizational Chart Dr. James Nabity Campus Liaison Dr. Donna Gerren Project Advisor ACES Lt. Carol Bryant AFRL Customer T.R. Mitchell Financial Lead Lucas Sorensen Project Manager Nicholas Taylor Systems Engineering Lead 68 ELECTRONICS TEAM Alex Bertman Electronics Lead Nicholas Moore Software Lead Alexander Johnson Electrical Hardware Lead MANUFACTURING & TESTING TEAM Jake Harrell Manufacturing Lead James Nguyen Structures Lead Matthew McKernan Testing and Safety Lead THERMAL MODELING TEAM Tristan Isaacs Heat Transfer Lead Matthew Robak Fluids Lead

69 Work Breakdown Structure Incomplete at CDR ACES Complete at CDR Course Deliverables Management Electronics Manufacturing Thermal Testing Systems Integration CDR FFR MSR TRR AIAA Paper Schedule WBS Risk Matrix Budget Spring Logistics PCB Design Software Architecture Software Development PCB Fabrication Software Verification Electronics Box Design Box Fabrication 1-D Models Solidworks Models Model Verification Test Result Analysis Cold Temp Battery Fuel Pump Characterization Main Heater Battery Insulation Fuel Pump Fuel Line Integrity HCU - FDS integration HCU - Electronics Housing Integration Full Systems Integration SFR HCU Verification HCU Operation Fuel Flow 69 PFR Final Integration Test

70 Work Plan - Gantt Chart Winter Break 70

71 Margin Critical Path 71 71

72 Cost Plan $

73 TestING Schedule and Planning Test to be Conducted Applicable Functional Requirements Date Scheduled Test Plan Complete Materials Acquired Test Complete HCU Cold Temp Battery /5/2017 Legend Main Heater Battery w/ Insulation 1.0 2/9/2018 Complete Fuel Pump Verification 2.1 2/23/2018 Fuel Line integrity 2.1 2/23/2018 In Progress Not Started HCU Operation 4.1, 4.2 3/23/2018 Full Box Integration and Validation 1 and 2 2.1, 2.2, 3.0 3/30/2018 & 4/6/

74 Conclusion CPE 1: Ensure that main heater battery is at or above the operational temperature (30 F), while not exceeding the maximum temperature (122 F). CPE 2: Heat the engine electronics (ECU, ESB, and engine battery) to their standard operating temperatures (60 F) while not exceeding a maximum temperature of 122 F for the battery and 150 F for the ECU and ESB. CPE 3: Control the temperature of the fuel lines and hopper and the mass flow rate of the fuel in order to provide fuel for start up procedure of engine. CPE 4: Construct a Heating Control Unit (HCU) which will control the fuel and electronics heating systems. Thermal Modeling shows capacity to meet Level 3 Success Heating and Electronics on track to meet Level 3 Success Testing analogs prepared to meet Level 3 Success On track for project success 74

75 ACknowledgements The team would like thank the following people for their assistance in this project. Donna Gerren Bobby Hodgkinson Dale Lawrence James Nabity Matt Rhode Trudy Schwartz Lee Huynh Timothy Kiley 75

76 76 Questions?

77 Sources Cengel, A. Yunus, Fundamentals of Thermal-Fluid Sciences, Engineering Toolbox, MATLAB pdetool SOLIDWORKS and SOLIDWORKS flow simulation Viscopedia, Polyurethane Tubing, Kanthal, tc/ Steady Heat Conduction, Electronics Cooling, Thermo Scientific Nalgene Bottles, INEOS, THERMAL CHARACTERIZATION OF LITHIUM-ION BATTERY CELL, page 112, Coordinating Research Council, HANDBOOK OF AVIATION FUEL PROPERTIES, 1983 CU REAPER Senior Projects Team,

78 78 Backup Slides

79 Index Presentation: Title Slide (1) Project Objectives (3) Design Solution (11) Critical Project Elements (17) Main Heater Battery (19) Electronics Box Heating (24) Heating Control Unit (38) Project Risks (52) Verification and Validation (58) Project Planning (67) Backup: Heating Wire (80) Thermal Model Verification (82) HCU (85) Initial Energy (89) ECU (102) Fuel Delivery System (105) FEM Setup (107) Transient Model (109) Verification and Validation (116) Thermal Model Animations (132) 79

80 Resistance Heating Wire Omega Resistance Heating Ribbon Wire NCCR ⅛ width,.0056 thickness, 100 ft length.88 Ω/ft Chosen using matlab code for heat production vs. wire model with ⅛ gaps between wire on elements. Code also accounted for temperature vs. current to ensure safe temperature levels 80

81 Heating Wire Analysis Total heating wire length for ⅛ width & ⅛ gaps was determined using surface area of components. Total resistance was determined using the resistance-per-foot value of.88ω/ft and wire lengths A set voltage of 22.2 V was used to find current and power Wire Length [ft] Total Resistance [Ω] Current [A] Power [W] Fuel Lines ft Ω Fuel Hopper ft Ω Temperature vs. Current data was only available for 1/64, 1/32, and 1/16 wire widths. However, at the 22.2 V, the temperature of these wires never reached problematic levels. Therefore, excess temperature was not a major concern. 81

82 Thermal Model Verification 82

83 Aluminum Block Test Block Initial Temperature: 22.0 C Water Initial Temperature: 0.0 C Test Time: 5 minutes 83

84 84 Aluminum Block SolidWorks Model

85 HCU BackUP Slides 85

86 86 HCU Altium Schematic

87 87 HCU Altium Schematic

88 LM317 Voltage Regulator Adjustable Voltage Regulator capable of regulating output voltage between 1.25V and 32V at greater than 1.5A Drops PWM voltage from LiPo Batteries from 22.2V to 6V for fuel pump Relevant Equations: V0 = Vref V0 = Vref*(1+R2/R1) + (Iadj*R2) Including Copper Heat Sink to prevent overheating 88

89 Initial Energy BackUP Slides 89

90 90 Cryogel Insulation Produced by Aspen Aerogels Uses Aerogel, a lightweight solid derived from a silica gel k=0.015 W/m*K =160 kg/m^3 10mm thickness Designed for low temperature applications

91 Internal Resistance of Battery Resistance for the heating load is Ω (assumes 22.2 V voltage drop across load) Voltage drop across internal resistive load is V Power dissipated by internal resistive load is W 91 The battery simulation was allowed to progress for 30 min with heat generation.

92 92 Internal Resistance of Battery

93 RC Circuit Equations Battery heat transfer 93

94 Management of Supercapacitors 1. The team will never charge the capacitor with higher voltage than 2.7 V. 1. The team will never handle a charged capacitor without proper safety equipment a. Thermal and electrical insulation will need to be worn Capacitors retain voltage for a long time after disconnected from circuit a. Our capacitor will take 3 hours to fully discharge

95 Initial Energy Requirements To heat batteries at a safe temperature takes 8 minutes In the 8 minute heating window, each circuit releases 1,442J, at an average 3W 8 circuits will provide 24W Peak wattage per RC circuit will be 3.65W 95

96 96 Initial Energy Circuit Design

97 Initial Energy Charging/Discharging Charging RC Circuit will be charged via wall outlet Single charging circuit for all 8 RC Circuits DPDT switch for each RC circuit Shift between charging and heating LED to signify capacitor is charging Discharging Grounding terminals from RC circuits Comparator with LED set to turn off when voltage falls below 0.025V 97

98 98 Initial Energy Charging Circuit

99 99 Initial Energy Discharge Circuit

100 Initial Energy RC Components SMAKN ACDC Power Adapter N-Channel MOSFET 60V 30A GTCAP Cold Starting Supercapacitor 2.7V 1200F 1 Ohm Resistor Wire Wound 5% Tolerance Taiyo Yuden Resistors Taiyo Yuden Capacitors TPS74401 Regulator 4 DPDT Heavy Duty Toggle Switches LEDs Texas Instruments Comparator 100

101 Risk of Supercapacitors Never charge a capacitor pasts its rated voltage. Shorting a capacitor will create a large amount of heat Can burn wire leads and fry other components Potential injury to personnel Capacitors retain voltage for a long time after disconnected from circuit From hours up to days 101

102 ECU BackUP Slides 102

103 ECU Heritage Custom ECU design provided by REAPER Hall Effect Sensor issues Mitigated by Andrew Quinn Schmitt Trigger Schematics available to team 103

104 Reaper ECU 104 Components: Atmega256A3-AU RS422 Recieiver/Transmitter FT230x USB-UART SD Card Holder NC7WZ17P6X Dual Buffers CMX60D20 Relay LT1761 Micropower Regulator CMOS Comparator PM05S Series Switching Regulator MAX31855KASA+ Thermocouple Driver Fuel Flow Sensor WE-2 Box Header 2SMX Oscillator LED s COM-00097Push Button Reset ISP Programmer Header MicroUSB Header Multiple Resistors, Capacitors, Diodes

105 Fuel Delivery System Backup Slides 105

106 106 Jet Fuel Viscosity vs Temperature

107 107 FEM Setup Slides

108 Solidworks Parameters Material Properties Material Nickel Chromium Aerogel Lithium Polymer Density (kg/m 3 ) Specific Heat (J/kg*k) Thermal Conductivity (W/m*k)

109 Transient Model BackUP Slides 109

110 Cooling of Electronics Box -40 F 110

111 Fuel Line Heating Feasibility 71 F 62 F 111

112 Fuel Line Heating Feasibility 62 F 112

113 Fuel Hopper Heating Analysis 62 F 113

114 Transient ELectronics Heating 62 F 114

115 Main Heater Battery Feasibility 0 F 115

116 Verification and Validation Backup Slides 116

117 Summary of Test Process Creation of Test and Safety Plan Review of Test and Safety Plan with PAB Test Setup and Operations Coordination Test Execution and Data Collection 117

118 Summary of Previous Tests Cold Battery Environmental Chamber Test Objectives: Verify that the cold temperature battery can provide voltage required to power the HCU in cold soak conditions Confirm that the test process outlined earlier provides the planning, preparation, and coordination needed for subsequent tests Prove the validity of the environmental chamber as a viable test bed for future project elements 118

119 Summary of Previous Tests Cold Battery Environmental Chamber Test Results: The cold temperature battery was shown to provide its nominal voltage (±0.1V) after being cold soaked at -50 F Demonstrated near identical (±5%) voltage and current draw on small motor when compared with power supply Full results shown in following slide 119

120 Summary of Previous Tests Cold Battery Environmental Chamber Test Result of accidental battery discharge via multimeter V V 120

121 Summary of Previous Tests Measuring Mass Flow Rate with Voltage Inputs Determined relationship between input voltage and mass flow produced by pump Relationship is Linear Linear Regression used to determine error in mass flow Error calculated: +/ g/s Determined upper bound for input voltage based on increased deviations from Linear Regression Upper voltage limit is 4.5 V 121

122 Dry Ice Test Bed Overview of Testbed: Cooler Internal Chamber Temperature of ~-50 F Ability to run fuel delivery system tests without risk of damaging expensive test equipment Applicable tests: Fuel lines integrity, HCU operation, Full box integration and validation Usable volume >> volume required for full scale electronics box Ability to accommodate required 8 channels of data transmission Q Useable Volume: 1932 in 3 Q 11.5 in ~½ Block of dry ice necessary for test chamber to reach -50 F Standard Block of Dry Ice: 10x10x2 in Dry Ice 14 in Q 122

123 Fuel Pump/Fuel Line Test Objective: Insulating Cover Determine the minimum operational temperature of the stock JetCat fuel pump DAQ Verify that the integrity of the fuel lines can be maintained in the cold soak conditions Test Overview: Cottonseed Oil: non-flammable, cost effective, readily available, freezing point of -55 F, faster more uniform heat transfer Ability to slowly lower the environment temperature while motoring component temperature and fuel mass flow rate ~2 ft Thermocouple Fuel Source Cottonseed Oil Fuel Pump Dry Ice Plastic Bag Power Fuel Sink DAQ Fuel Flow Meter 123

124 Fuel Pump Test Objective: Determine the if the minimum operational temperature of the stock JetCat fuel pump is above -50 F. DAQ Dry Ice Insulating Cover Test Overview: Plastic Bag Submerge the fuel pump in the cottonseed oil bucket at room temperature and begin to pump fuel Insert dry ice blocks into bucket to lower the temperature of the fluid Monitor fluid temperature and fuel flow rate until the flow meter registers a flow rate outside desired 4.8 ± 0.1 g/s Assuming 2.5 gallons of cottonseed oil (freezing temp of -55 F), approximately 39.1 lbs or 4 blocks of dry ice is needed to lower the temperature of the oil to -50 F ~2 ft Thermocouple Fuel Source Cottonseed Oil Fuel Pump Power DAQ Fuel Sink Fuel Flow Meter 124 Required bucket volume of ~6 gallons

125 Fuel Line Test Objective: Determine the if the minimum operational temperature of the stock fuel lines is above -50 F. DAQ Dry Ice Insulating Cover Test Overview: Submerge the fuel pump and lines in the cottonseed oil bucket at room temperature and begin to pump fuel Insert dry ice blocks into bucket to lower the temperature of the fluid Visually examine fuel lines for cracks and bulges. ~2 ft Thermocouple Fuel Source Plastic Bag Fuel Pump DAQ Fuel Flow Meter Visually examine bag containing the fuel pump and lines for extra fuel. Fuel inside the bag could indicate a leak. Cottonseed Oil Power Fuel Sink 125

126 Main Heater BAttery Test Main Heater Battery Environmental Chamber Test Objectives: Verify that the main heater battery can provide voltage required to power the FDS and EHS in cold soak conditions Validate thermodynamic models Insulation Test Overview: Identical to the Cold Temperature Battery test with added temperature recording Omega Model HH2 Type J-K Thermocouple w/ Digital Readout 126

127 Test Chamber Calculations Dry Ice Chamber 8.36 gallons of air = kg 1 block of dry ice = 10 lbs = kg Surface temp of dry ice = -109 F = K Need ambient air final temp of -50 F (227.6 K), start at room temp of 70 F (294.3 K) K = kg/( kg + x) * (294.3 K) + x/( kg + x) * (194.7 K) x = x x = => kg of Dry Ice Needed = lbs or 1/2 Block of Dry Ice 127

128 Test Chamber Calculations Cottonseed Oil Test Chamber 2.5 gallons of cottonseed oil = kg CSO =0.925 g/cm^3 1 block of dry ice = 10 lbs = kg Surface temp of dry ice = -109 F = K Need cottonseed oil final temp of -50 F (227.6 K), start at room temp of 70 F (294.3 K) K = kg/( kg + x) * (294.3 K) + x/( kg + x) * (194.7 K) x = x 32.95x = x => kg of Dry Ice Needed = lbs or 4 Blocks of Dry Ice 128

129 Test Instrumentation Temperature Sensors Test Bed Environment Temperature: 1 Omega Model HH22 Type J-K Thermocouple Accuracy of ±0.05 F Individual Component Temperature: DAQ capable of supporting up to 8 individual temperature sensors 129

130 Test Instrumentation Mass Flow Sensor Equflow 0045 Readily Available, $50 pack of disposable inserts Flow Rate 0.1-2L/min with 110,000 pulses/l Engine fuel flow rate: L/min Accurate to 1% of reading (± L/min) 34mA current at 5V If the interface with the microcontroller is not possible then mass flow will be calculated via pressure potential function utilizing applied voltage and temperature. 130 *Information courtesy of CU REAPER senior projects team

131 Test Instrumentation Data Acquisition System (DAQ) National Instruments DAQ USB-6009 Analog Input (8 inputs): +/-10V, accuracy 7.73mV +/-1V, accuracy 1.53mV 12 Bit On-campus resource, readily available 131

132 Thermal Model Animations 132

133 133 Cooling

134 134 Heating